Unless otherwise indicated herein, approaches described in this section are not prior art to the claims listed below and are not admitted as prior art by inclusion in this section.
There are various well-developed and well-defined cellular communications technologies in telecommunications that enable wireless communications using mobile terminals, or user equipment (UE). For example, the Global System for Mobile communications (GSM) is a well-defined and commonly used communications system, which uses time division multiple access (TDMA) technology, which is a multiplex access scheme for digital radio, to send voice, video, data, and signaling information (such as a dialed telephone number) between mobile phones and cell sites. The CDMA2000 is a hybrid mobile communications 2.5G/3G (generation) technology standard that uses code division multiple access (CDMA) technology. The UMTS (Universal Mobile Telecommunications System) is a 3G mobile communications system, which provides an enhanced range of multimedia services over the GSM system. The Long-Term Evolution (LTE), as well as its derivatives such as LTE-Advanced and LTE-Advanced Pro, is a standard for high-speed wireless communication for mobile phones and data terminals. In addition, there are some newly developed next generation communication technologies such as 5th Generation (5G), New Radio (NR), Internet of Things (IoT) and Narrow Band Internet of Things (NB-IoT). These communication technologies are developed for higher speed transmission and serving for huge number of devices including machine type devices.
In some scenarios, when the UE is powered on or tries to recover from an out of service state, the UE may need to find a suitable cell of a public land mobile network (PLMN) to camp on. The UE may have to perform a frequency scan procedure to find the suitable cell. However, if the UE is not aware of the location (e.g., country or area) of the UE, the UE may not know which frequency bands should be searched first. The UE may only have to perform full-band search for all frequency bands supported by the UE. The full-band search procedure usually take significant long time and may consume significant power of the UE. This may degrade the user experiences. In a worse case, some frequency bands may not be supported or deployed in some countries. The UE may even spend unnecessary time and power to scan those un-supported frequency bands. If the UE can get the location information or the mobile country code, the UE may be able to determine the supported frequency bands in that country or area and may only scan the supported frequency bands.
Accordingly, it is important for the UE to get the location information or the mobile country code to camp on a cell quickly and save power consumption. Therefore, it is needed to provide a mechanism for recognizing the mobile country code.